The invention pertains to polymeric materials. More specifically, the invention is directed to specific blends of polymers, which can be mixed on a molecular level.
In the art so called high-performance polymers (HPPs) are known. These are typically all-aromatic polymers, such as liquid crystal polymers (LCP), polyethersulfone (PES), polyimide (PI), polyetherimide (PEI), polyetheretherketone (PEEK), polyetherketoneketone (PEKK), polyphenylene sulfide (PPS) or polyaryletherketone (PAEK).
It has been suggested to use non-reactive, high molecular weight LCPs to modify high-performance polymers (HPPs) such as PPS (see for instance Gopakumar et al., Polymer 39(1998)2221-2226), PES (see e.g. He et al., Polymer 35(1994)5061-5066), PEI, PEEK (e.g. Goel et al., Materials and Manufacturing Processes 16(2001)427-437) or PEKK, in particular to improve the processability of these polymers and to obtain “molecular composites” with improved thermo-mechanical behavior. Although processing could indeed be improved it was found that the HPPs appear to form incompatible molten phases with the LCPs. Upon cooling the melt separates in two distinct phases (HPP and LCP). As a result this method can not be used to prepare molecular composites wherein the LCP is a molecular dispersed reinforcement.
It is an object of the invention to provide polymeric compositions comprising HPPs that do not suffer from phase separation as in the prior art. It is a further object of the present invention to provide such compositions wherein the mechanical properties of the HPPs are improved.